Metallurgical furnace and method of transporting commodities therein

ABSTRACT

A METALLUGICAL FURNACE WHEREIN A SUPPORT CARRIES SEVERAL PARALLEL BEAMS WHICH EXTEND BETWEEN THE INLET AND THE OUTLET OF THE HEATING CHAMBER. EACH BEAM COMPRISES TWO LONGITUDINALLY EXTENDING PORTION S EACH OF WHICH EXTENDS THE FULL LENGTH OF THE RESPECTIVE BEAM AND BOTH OF WHICH ARE MOVABLE ANGULARLY WITH REFERENCE TO THE SUPPORT.ONE PORTION OF EACH BEAM IS ALSO MOVABLE FORWARDLY (TOWARD THE OUTLET) AND BACKWARDS (TOWARD THE INLET) RELATIVE TO THE OTHER PORTION OF THE RESPECTIVE BEAM. INGOTS, SLABS, BILLETS OR LIKE METALLIC BLANKS ARE PLACED ONTO THE BEAMS WHILE THE BEAMS ASSUME SUCH ANGULAR POSITIONS THAT THE BLANKS COME TO REST ON THE OTHER PORTION OF EACH BEAM, THE BEAMS ARE THEREUPON ROTATED TO TRANSFER THE BLANKS ONTO THE ONE PORTION OF EACH BEAM AND SUCH ONE PORTION IS THEN MOVED FORWARDLY TO TRANSPORT THE BLANKS TOWARD THE OUTLET. THE PROCEDURE CAN BE REPEATED AS OFTEN AS NECESSARY BY ROTATING THE BEAMS TO TRANSFER THE BLANKS ONTO THE OTHER PORTION OF EACH BEAM, BY MOVING THE ONE PORTION OF EACH BEAM BACKWARDS, BY ROTATING THE BEAMS TO TRANSFER THE BLANKS ONTO THE THUS RETRACTED ONE PORTION OF EACH BEAM, AND BY MOVING THE ONE PORTION OF EACH BEAM FORWARDLY.

March 2., 1971 KNAAK 3,567,197

' METALLURGICAL FURNACE AND METHOD OF TRANSPORTING COMMODITIES THEREIN v Filed April 8. 1969 3 Sheets-Sheet 1 March 2, 1971 R. KNAAK 3,567,197

METALLURGICAL FURNACE AND METHOD OF TRANSPORTING COMMODITIES THEREIN Filed April 8. '1969 3 Sheets-Sheet 3 Fig.6 A35 run-m rule mm: ce-n [CUM/L March 2, 1971 KNAAK I R. METALLURGICAL FURNACE AND MET COMMODITIES THE Filed April 8. 1869 r D OF TRANSPORTING 3 SheetsSheet 2 rwew gnome lam! flame/l. M11 40 United States Patent 3,567,197 METALLURGICAL FURNACE AND METHOD OF TRANSPORTING COMMODITIES THEREIN Riidiger Knaak, Neuss, Germany, assignor to Koppers- Wistra-Ofenbau Gesellschaft mit beschrankter Haftung,

Dusseldorf, Germany Filed Apr. 8, 1969, Ser. No. 814,415 Claims priority, application Germany, Apr. 9, 1968, P 17 58 139.4 Int. Cl. F27b 9/14 US. Cl. 263-6 23 Claims ABSTRACT OF THE DISCLOSURE A metallurgical furnace wherein a support carries several parallel beams which extend between the inlet and the outlet of the heating chamber. Each beam comprises two longitudinally extending portions each of which extends the full length of the respective beam and both of which are movable angularly with reference to the support. One portion of each beam is also movable forward- 1y (toward the outlet) and backwards (toward the inlet) relative to the other portion of the respective beam. Ingots, slabs, billets or like metallic blanks are placed onto the beams while the beams assume such angular positions that the blanks come to rest on the other portion of each beam; the beams are thereupon rotated to transfer the blanks onto the one portion of each beam and such one portion is then moved forwardly to transport the blanks toward the outlet. The procedure can be repeated as often as necessary by rotating the beams to transfer the blanks onto the other portion of each beam, by mov ing the one portion of each beam backwards, by rotating the beams to transfer the blanks onto the thus retracted one portion of each beam, and by moving the one portion of each beam forwardly.

BACKGROUND OF THE INVENTION The present invention relates to a method and apparatus for transporting commodities, particularly to a method and apparatus for transporting metallic billets, slabs, ingots or like bulky bodies or blanks from the inlet toward the outlet of the heating chamber in a metallurgical furnace. Still more particularly, the invention relates to a method and apparatus for stepwise transport of commodities through a heating chamber or the like.

Presently known furnaces which can be utilized for heat treatment of metallic blanks while such blanks move from the inlet toward the outlet of a heating chamber which is maintained at an elevated or extremely high temperature include so-called pusher furnaces, walking beam furnaces, tunnel furnaces and rolling grate furnaces. Each such furnace exhibits certain advantages over the other types and each thereof exhibits one or more drawbacks. For example, pusher type furnaces are very satisfactory for heating of steel blanks which are to be used in rolling. Such furnaces are sturdy and their movable blank-engaging parts can be provided with inserts or attachments of metallic material to prevent unequal heating of blanks, namely, to prevent underheating of those portions of a blank which come in direct contact with the movable parts of the furnace. A drawback of pusher type furnaces is that their length depends on the dimensions of transported commodities. Furthermore, evacuation of the heating chamber in a pusher type furnace presents serious problems.

The so-called walking beams are very satisfactory in underfiring furnaces. As a rule, the walking beams are or include elongated water-cooled rails which are mounted on water-cooled supports. The length of walking beams Patented Mar. 2, 1971 ice can be selected at will and they can be used for transport of very small as well as of exceptionally bulky metallic bodies. Furthermore, the heating chamber can be evacuated with little loss in time in either direction, i.e., by way of the inlet or by way of the outlet. A drawback of walking beam furnaces is that they must be provided with two sets of beams and with two sets of supports, one for the stationary beams and one for the walking beams; this results in considerable losses in heat energy because all of the supports and beams must be cooled with circulating water which removes large quantities of heat. Furthermore, the parts of a walking beam furnace are subjected to substantial stresses, especially when the blanks are deposited on stationary beams and/ or picked up by walking beams. In order to resist such stresses, the parts must be overdimensioned; nevertheless, stressing during deposition and pickup of blanks causes substantial wear on the heat-insulating parts, particularly on those which consist of ceramic material. Due to such stressing, the metallic inserts which carry the blanks during transport through the heating chamber must be made of high-quality metallic material which contributes to initial and maintenance cost of the furnace. The energy requirements of a walking beam furnace are rather high, especially when the furnace is to be used for transport of bulky commodities, because such bulky commodities must be accelerated and decelerated with little loss in time and at frequent intervals in order to insure that the output of the furnace does not drop below a certain economically acceptable minimum value.

Tunnel furnaces employ carriages or dollies which transport the commodities through the heating chamber. Such dollies or carriages normally extend the full width of the heating chamber and they must be heated to the same temperature as the transported blanks which results in consumption of large quantities of heat energy. If the furnace is provided with recuperators which recover heat from the carriages, the auxiliary equipment occupies much room and contributes to the initial as well as maintenance cost. Still further, the carriages must be transported from the outlet and back to the inlet along the exterior of the furnace; this contributes significantly to the bulk of a tunnel furnace. Additional problems arise when the tunnel furnace must be designed as an underfiring furnace.

Rolling grate furnaces of conventional design cannot be used if the temperature of transported material should exceed a certain value. Also, conventional rolling grate furnaces cannot be used if the surfaces of conveyed blanks should be free of impressions or other marks which are likely to develop when a heated blank rests on rolling grates whose external surfaces rapidly accumulate uneven layers of scale, cinder or other foreign matter.

SUMMARY OF THE INVENTION An object of my invention is to provide a novel and improved method of transporting large or small metallic blanks or other commodities in a predetermined direc tion, with minimal expeditures in energy, without damaging the surfaces of conveyed commodities, and in an automatic or semiautomatic way.

Another object of the invention is to provide an improved metallurgical furnace which does not exhibit the above enumerated drawbacks of conventional furnaces and which can be used for treatment and transport of commodities which must be maintained at relatively low, medium high or exceptionally high temperatures.

Still another object of the invention is to provide a method of stepwise transporting commodities through increments of desired length.

An additional object of the invention is to provide an apparatus which preferably forms part of a metallurgical furnace and which can be utilized to carry out the above outlined method.

A further object of the invention is to provide an apparatus which can transport one or more commodities at a time, which can transport the commodities in such a way that the spacing between successively transported commodities remains unchanged, and which can be utilized in overfiring, underfiring or over-and-under firing metallurgical furnaces.

An ancillary object of the invention is to provide an apparatus which can be installed in presently known metallurgical furnaces to replace walking beams, carriages, rolling grates or analogous conventional transporting means.

Still another object of the invention is to provide a transporting apparatus which can stand extensive use at elevated temperatures, which is less likely to mar the surfaces of commodities than the aforementioned conventional apparatus, which can be used for gradual, continuous or stepwise transport of commodities, and which permits rapid and convenient evacuation of commodities from the transporting area, for example, from the heating chamber in a metallurgical furnace.

One feature of my invention resides in the provision of a method of transporting commodities, particularly of transporting metallic ingots, slabs, billets or like blanks from the inlet to the outlet of the heating chamber in a metallurgical furnace, by means of at least one pair of supporting surfaces one of which is rotatable about a predetermined axis and the other of which is rotatable with the one surface and is movable forwardly and backwards relative to the one surface in the direction of the axis. The method comprises the first step of placing a commodity onto the one surface, the second step of rotating the surfaces through an angle of such magnitude that the commodity comes to rest on the other surface, and the third step of moving the other surface forwardly with reference to the one surface to thereby transport the commodity in the direction of the axis.

The method preferably further comprises the steps of rotating the surfaces through an angle of such magnitude that the commodity again comes to rest on the one surface, and thereupon moving the other surface backwards with reference to the commodity and the one surface.

The step of rotating the surfaces may be carried out while the axis is stationary or while the axis moves sideways, i.e., the surfaces roll along a support if the axis moves sidesways or the surfaces turn about a fixed axis if the beams which are provided with such surfaces are held against sidewise movement.

If the commodity is to be transported stepwise in two, three or more stages, the method further comprises the fourth step of rotating the surfaces through such an angle that the commodity comes to rest again on the one surface, the fifth step of moving the other surface backwards with reference to the one surface, and thereupon repeating the second, third, fourth and fifth steps as often as necessary to thereby move the commodity through a desired multiple of the extent of forward movement of the other surface. As a rule, the commodities are simultaneously transported by two or more pairs of surfaces. Thus, the transporting apparatus which is utilized for practicing of my method may comprise two or more elongated parallel beams which extend between the inlet and the outlet of the heating chamber and each of which comprises as first portion provided with the one surface and a second portion provided with the other surface. The beams are rotatable with reference to their support to thereby move their portions between first and second positions in which the commodities respectively rest on the one and the other surface of each beam, and the second portions of the beams are movable forwardly and backwards relative to the corresponding first portions to transport the commodities toward the outlet during forward movement and to return to starting positions while moving backwards and while the commodities rest on the first portions.

The novel features which are considered as characteristic of the invention are set forth in particular in the appended claims. The improved transporting apparatus itself, however, both as to its construction and its mode of operation, together with additional features and advantages thereof, will be best understood upon perusal of the following detailed description of certain specific embodiments with reference to the accompanying drawing.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1a is a schematic fragmentary transverse vertical sectional view of a metallurgical furnace including a transporting apparatus which is constructed and assembled in accordance with a first embodiment of my invention and comprises several parallel beams of circular crosssectional outline;

FIG. 1b is a similar sectional view but showing the beams in a different angular position;

FIG. 2 is a transverse vertical sectional view of a beam which forms part of a second transporting apparatus;

FIG. 3 is a fragmentary transverse vertical sectional view of a third apparatus having a beam which is turnable about a fixed axis;

FIG. 4 is a plan view of the structure shown in FIG. 3;

FIG. 5 is a transverse vertical sectional view of still another beam; and

FIG. 6 is a schematic transverse vertical sectional view of an additional beam.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring first to FIGS. 1a and 1b, there is shown a portion of an apparatus which is installed in an underfiring furnace and serves to transport metallic blanks 1 or analogous commodities from the inlet to the outlet of a heating chamber in the furnace. The inlet is located in front and the outlet is located behind the plane of FIGS. 1a and lb. The apparatus comprises basically a support 4 which is fixedly mounted in a median portion of the heating chamber and carries two or more parallel beams A and B each having two elongated portions 2 and 3. In the embodiment which is shown in FIGS. 1a and 1b, the beams A and B are of circular cross-sectional outline and can roll, preferably Within limits, along the top surface of the support 4, i.e., the axes of the beams A and B can move sideways. The portions 2, 3 of the beams A and B have convex external surfaces 2a, and 3a which together form a substantially complete cylindrical surface. In order to transport a commodity 1 from the inlet toward the outlet, the commodity is placed onto the beams A and B while the beams assume the angular positions shown in FIG. la, i.e., the commodity comes to rest on the surfaces 2a of the portions 2. The beams A and B are thereupon caused to rotate about their axes while the axes move sideways until the beams reach the angular positions shown in FIG. 1b in which the commodity rests on the surfaces 3a of the portions 3. The portions 3 are movable forwardly and backwards with reference to the portions 2, i.e., at right angles to the plane of FIGS. 1a and 1b, to transport the commodity 1 toward the outlet while the beams A and B assume the angular positions shown in FIG. lb. The beams are thereupon rolled back to the positions shown in FIG. la so that the commodity 1 is transferred onto the surfaces 2m and the portions 3 are caused to move backwards, namely, toward the observer of FIG. 1a, so as to reassume their starting positions. The beams A and B are then rolled to assume the positions shown in FIG. lb and the portions 3 are moved forwardly (away from the observer of FIG. 1b) to advance the commodity by a second step. The same procedure can be repeated as often as necessary in order to move the commodity through a distance which is a multiple of the extent of forward movement of the portions 3 with reference to the portions 2. The portions 2 are held against lengthwise movement and their length preferably equals or approximates the length of portions 3. The means for rolling the beams A and B may cornprise hydraulic cylinder and piston units (not shown) whose piston rods are coupled to trunnions extending axially beyond the ends of the portions 2. The piston rods can move back and forth in a horizontal plane in parallelism with the top surface of the support 4 to thereby move the beams A and B between the positions shown in FIGS. 1a and 1b. The means for moving the second portions 3 lengthwise of the corresponding first portions 2 may include rack and pinion drives (not shown) or any other suitable devices capable of reciprocating the portions 3 in the positions shown in FIGS. 1a and 1b. The space C below the support 4 constitutes the lower portion of a heating chamber and can be heated, i.e., the beams A and B can be installed in an underfiring metallurgical furnace.

FIG. 2 illustrates the details of a modified beam D which can replace either one of the beams A, B shown in FIGS. la and lb. The first portion 5 of the beam D is rotatable or turnable about an elongated axis which is parallel to the longitudinal direction of the beam D, i.e., the portion 5 corresponds to the first portion 2 of the beam A and B. The second portion 6 corresponds to one of the portions 3. The portions 5 and 6 are hollow and contain supplies of water or other suitable coolant. The beam D further comprises friction reducing means which are interposed between the portions 5, 6 to insure that the portion *6 can be moved lengthwise of the portion 5 in response to exertion of a relatively small force. Such friction reducing means comprises a cage 7 which confines balls 8 or analogous rolling elements. The portion 5 includes an elongated guide rail 9 which extends into the interior of the hollow second portion 6 and is attached to the remaining major part of the portion 5 by longitudinally spaced connecting elements or webs 10. The numerals 11 denote extensions or attachments which are provided on the portions 5, 6 and serve as a means for directly supporting one or more commodities (not shown). Such extensions or attachments 11 preferably consist of a metallic material which is resistant to wear and can stand elevated temperatures. Ribs 12 on the portions 5, 6 extend into complementary longitudinally extending grooves of the extensions 11 to insure that such extensions share all movements of the corresponding portions 5 and 6. Thus, the left-hand extension 11 must share all angular movements of the first portion 5 and the right-hand extension 11 shares all angular and lengthwise movements of the second portion 6. The ribs 12 are preferably welded to the water-cooled main parts of the corresponding portions 5 and 6 and to the extensions 11. An inclined bafile 13 of sheet metal or the like is installed between the webs 10 to deflect ashes, cinder, scale and other foreign matter which descends in thenarrow gap 60 between the portions 5 and 6. Such batfle deflects foreign matter away from the cage 7 so that the foreign matter cannot contaminate the friction reducing means including the rolling elements 8. The portions 5, 6 further include external jackets 14 of heat insulating material, such as a ceramic or the like. These jackets surround the internal passages of portions 5, 6 which contain circulating Water. The ribs 12 and extensions 11 are not insulated to make sure that the commodity which rests on the one or the other extension 11 is not subjected to localized cooling action, i.e., the extensions 11 are preferably heated to the temperature of the surrounding atmosphere to insure that each zone of the transported commodity is heated to the same extent. The gap 60 between the portions 5 and 6 is rather narrow (especially at the upper ends of the extensions 11, as viewed in FIG. 2) to reduce the likelihood of penetration of foreign matter into the region of the baflle 13 and webs 10.

The mode of operation of the apparatus which employs two or more beams D of the type shown in FIG. 2 is analogous to operation of the apparatus shown in FIGS. la and 1b. The first portion 5 can turn or roll about an axis which is parallel to the longitudinal direction of the beam D, and the second portion 6 shares all angular movements of the first portion 5. In addition, the second portion 6 is movable forwardly and backwards, along the rail 9, so as to transport one or more commodities when such commodities rest on the exposed surface of the righthand extension 11, and while the second portion 6 moves forwardly. The second portion 6 moves backwards while the commodity or commodities rest on the exposed surface of the extension 11 which is secured to the rib 12 of the first portion 5.

The beam D of FIG. 2 may comprise six rows of rolling elements 8, i.e., three rows close to the top and three rows close to the lower part of the rail 9. Such mounting of the second portion 6 permits for proper lengthwise movement with reference to the portion 5 even if the rail 9 and/ or the portion 6 is twisted or otherwise deformed in response to uneven heating.

The axis about which the beam D of FIG. 2 turns is preferably closely adjacent to the ribs 12. The centers of curvature of the convex surfaces of the extensions 11 are preferably located on such axis; this insures that the commodities need not be lifted or lowered when the beam D turns to transfer the commodities from the left-hand extension 11 onto the right-hand extension or vice versa. In other words, the commodities preferably remain at the same level all the way during transport through the furnace, even if they must be transported in a series of stages so that the beam D must turn back and forth between successive backward movements of the second portion 6.

FIGS. 3 and 4 illustrate a portion of a third apparatus wherein the beams E (only one shown) are turnable about a fixed axis defined by several hollow tubular supports 15 which extend at right angles to the direction of transport of commodities. The friction reducing means between each support 15 and the beam E comprises a pair of rollers 16 whose axes are parallel to the longitudinal direction of the beam E and which are mounted in suitable sockets provided therefor in the support 15. The first portion 17 of the beam E comprises an arcuate runner 18 which rests on and can roll with reference to the elements 16. The longitudinally movable second portion 17a of the beam E is arranged to travel along a guide rail 9 which is secured to the first portion 17 by webs 10'. The extensions are shown at 20, and the numerals 21 denote the insulation on the support 15 and portions 17, 17a. The numeral 19 denotes the gap between the portions 17, 17a. At least the support 15 is cooled by circulating water. The arrangement is such that water which flows in the interior of the support 15 also cools the friction reducing rolling elements 16 and hence the runner 18 of the first portion 17. The longitudinal axis of the beam E is shown at 19A; the center of the curvature of the convex external surface of the runner 18 is located on this axis.

An important advantage of the apparatus which includes two or more beams E of the type shown in FIGS. 3 and 4 is that a relatively small angular displacement of the beam suffices to transfer a commodity from the exposed convex surface of the extension 20 on the first portion 17 onto the convex surface of the extension 20' on the second portion 17a or vice versa. The centers of curvature of the exposed convex surfaces of extensions 20 are also located on the axis 19A. In FIG. 3, the extensions 20- are shown as forming integral parts of the portions 17, 17a; however, it is equally within the purview of my invention to produce the extensions 20 separately and to weld or otherwise connect such separately produced extensions to the corresponding portions of the beam.

In FIG. 4, the phantom line 50 indicates a portion of a heating chamber in a metallurgical furnace. This chamber 50 has an inlet 51 and an outlet 52.

FIG. shows a portion of a further beam F which includes a first portion 22 (corresponding to the first portion 2 of the beam A or B) and a longitudinally movable second portion 28. Bolts, webs or analogous connecting elements 23 are employed to connect the first portion 22 with a water-cooled holder 24 whose walls 25 are reinforced by ribs 26. The extensions 27 are welded to upwardly extending ribs of the portions 22 and 28 and define between themselves a narrow gap for descent of foreign matter. The second portion 28 carries a set of lower friction reducing rollers 29 which rotate about horizontal axes (when the beam F assumes the position in FIG. 5) and move along a rail 30 of the holder 24. Additional friction reducing rollers 31 which rotate about vertical axes are provided on the second portion 28 and travel in grooves provided therefor in the upper portion of the holder 24. The compartment 32 in the lowermost part of the holder 24 serves as a depository for foreign matter which penetrates through the gap between the extensions 27 and into the water-cooled interior of the beam F. The upper side of the holder 24 is open and the longitudinally movable second portion 28 of the beam F is received in the water-cooled space of the holder 24. The cooling ribs 26 can be provided at the inner and at the outer sides of the walls 25. The first portion 22 and the holder 24 are provided with insulating jackets 22a, 24a. The walls 25 are preferably thin to prevent excessive twisting or other deformation of the holder 24 in the event that the insulating jacket 24a becomes loose or is completely separated from the holder.

If desired, the two relatively movable portions of a beam can be designed in such a way that they are in full surface-to-surface contact with each other. This prevents penetration of foreign matter into the interior of the beam. One such beam is shown at G in FIG. 6. The first portion 33 is hollow and accommodates a supply of circulating water or other coolant. The extension 34 of the first portion 33 is provided with a T-groove for a tongue 36 of an extension 35 which constitutes the longitudinally movable second portion of the beam G. The gap between the portions 33, 35 is extremely narrow or is eliminated in its entirety.

The manner in which the beams of FIGS. 5 and 6 can move angularly and in which their second portions 28, 35 move lengthwise of the first portions 22, 33 is the same as described in connection with FIGS. 1a, 1b and 2.

When compared with a conventional pusher type furnace, the furnace which embodies the transporting apparatus of my invention exhibits several important advantages, namely: The heating chamber of the improved furnace can be evacuated very rapidly and in either direction. Also, the furnace can be designed for transport of very small or very bulky commodities as well as for simultaneous or alternating transport of differently dimensioned commodities. The improved furnace also constitutes a substantial improvement over walking beam furnaces because it comprises a smaller number of parts and, therefore, its heat energy requirements are much lower. The beams of my improved furnace do not interfere materially with heating of workpieces from below, i.e., the so-called shadows which are cast by the transporting parts onto the commodities which are transported in an underfiring furnace are reduced to a minimum. The small number of parts in my furnace allows for more uniform heating of commodities, not only from above but also from below.

Another important advantage of the improved furnace is that the longitudinally movable second portions of the beams can be supported and guided by the first portions, namely, by those portions which can turn but do not or cannot move lengthwise of the respective beams. This renders it possible to employ relatively lightweight beams because the first portion of each beam serves as a support and guide for the second portion and because the second portions constitute reinforcing elements for the first portions. The quantity of insulating material for the beams is also reduced because the spaces between the first and second portions of the beams need not be insulated at all.

Since the mass of parts which constitute the improved transporting apparatus is less than the mass of parts in a tunnel furnace, the heat energy requirements of the furnace which embodies my apparatus are considerably lower than the consumption of heat energy in a tunnel furnace. Also, the apparatus of my invention need not be provided with heat recuperating means which reduces its initial and maintenance cost.

In comparison with conventional rolling grate furnaces, the furnace which embodies my apparatus also exhibits several important advantages. For example, the ratio of blank-supporting surfaces to the area of insulated surfaces is more satisfactory. As a rule, the entire exterior of each rolling grate must be provided with a highquality metallic layer because each portion of such layer is likely to come into contact with transported goods. In my apparatus, only the relatively small extensions of the first and second portions of each beam are intended to come into contact with the transported goods; therefore, the expenditures for high-quality material of extensions are much lower. The major part of each beam in my apparatus can be surrounded by insulation so that the cost of such beams is but a fraction of the cost of a rolling grate.

Referring again to walking beam furnaces, the improved apparatus exhibits the additional important advantage that the transfer of commodities from the first onto the second portions of beams or vice versa can be effected practically without any shocks so that the beams are subjected to negligible wear and can stand much longer use than the beams of a walking beam furnace. Furthermore, the energy requirements of a drive which must rotate the beams of my apparatus and which must move the second portions of my beam lengthwise of the first portion are much lower than the energy requirements of a drive in a walking beam furnace wherein the movable beams must be moved up and down, forwardly and backwards, and must actually carry and lift the total weight of two or more ingots, slabs or like commodities. Absence of appreciable shocks is particularly important as regards the useful life of insulation on the beams.

Without further analysis, the foregoing will so fully reveal the gist of the present invention that others can, by applying current knowledge, readily adapt it for various applications without omitting features which fairly constitute essential characteristics of the generic and specific aspects of my contribution to the art.

What is claimed as new and desired to be protected by Letters Patent is set forth in the appended claims:

1. A method of transporting commodites, particularly of transporting metallic blanks from the inlet to the outlet of a heating chamber, by means of two supporting surfaces one of which is rotatable about a predetermined axis and the other of which is rotatable with the one surface and is movable forwardly and backwards relative to the one surface in the direction of said axis, comprising the first step of placing a commodity onto the one surface; the second step of rotating the surfaces through such an angle that the commodity comes to rest on the other surface; the third step of moving said axis sideways simultaneously with said second step; and the fourth step of moving the other surface forwardly with reference to the one surface.

2. A method as defined in claim 1, further comprising the steps of rotating the surfaces through such an angle that the commodity comes to rest on the other surface; the moving the other surface backwards with reference to the one surface.

3. A method as defined in claim 1, further comprising the fifth step of rotating the surfaces through such an angle that the commodity comes to rest on the one surface, the sixth step of moving the other surface backwards with reference to the one surface, and thereupon repeating said second, third, fifth and sixth steps to thereby move the commodity through a desired multiple of the extent of forward movement of the other surface.

4. A method as defined in claim 1, further comprising the step of simultaneously transporting the commodity by at least two additional surfaces respectively corresponding to said one and said other surface and moving in synchronism with the first mentioned surfaces.

5. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; and a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams, said beams being arranged to roll along said support means during movement between said first and second positions thereof.

6. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; and a plurality of substantially parallel enlongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams, each of said beams further comprising friction reducing means interposed between said first and second portions thereof.

7. Apparatus as defined in claim 6, wherein at least one portion of each beam extends along the full length of the respective beam.

8. Apparatus as defined in claim 6, wherein said axes are fixed.

9. Apparatus as defined in claim 6, further comprising a heating chamber accommodating said support means and said beams and having a portion extending below said support means to permit underfiring.

10. Apparatus as defined in claim 6, wherein at least one portion of each of said beams is hollow and further comprising a supply of coolant in said one portion.

11. Apparatus as defined in claim 6, wherein at least one portion of each beam comprises a metallic extension arranged to carry the commodity in the corresponding position of the respective beam.

12. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams; and fric- 10 tion reducing means interposed between said support means and said beams.

13. Apparatus as defined in claim 12, wherein the first and second portions of said beams are in surface-tosurface abutment with each other.

14. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; and a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the re spective first portions to transport the commodity during forward movement in the second positions of said beams, each of said portions comprising a cooled part and a metallic extension having a surface which comes into direct contact with the commodity in the respective position of the corresponding beam.

15. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; and a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams,.each portion of each of said beams comprising a metallic extension which comes into direct contact with commodities in the respective angular position of the corresponding beam, said metallic extensions defining between themselves gaps for descent of foreign matter.

16. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; and a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and back-wards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams, the first portion of each beam comprising a cooled lower part and an upper part constituting a metallic extension which comes into direct contact with the commodity in the first position of the respective beam.

17. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams, the first portion of each beam comprising a guide rail for the corresponding second portion; and antifriction means interposed between said second portions and the corresponding rails.

18. Apparatus as defined in claim 17, wherein each of said first portions further comprises a main part and webs connecting the main part with the respective rail.

19. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; and a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams, each of said beams being of substantially circular cross-sectional outline and being arranged to roll along said support means between said first and second positions thereof, said axes being the longitudinal central axes of the respective beams.

20. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means comprising internally cooled supports; a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions 12 to transport the commodity during forward movement in the second positions of said beams; and friction reducing rolling elements mounted in said supports and supporting said beams for angular movement.

21. Apparatus for transporting commodities, particularly for transporting metallic blanks from the inlet to the outlet of a heating chamber, comprising support means; and a plurality of substantially parallel elongated beams carried by said support means, each of said beams comprising a first and a second longitudinally extending portion and said beams being rotatable about axes which are substantially parallel thereto between first and second angular positions in which a commodity which is deposited onto said beams is respectively carried by the first and second portions of said beams, said second portions being movable forwardly and backwards lengthwise of the respective first portions to transport the commodity during forward movement in the second positions of said beams, said first portions comprising fluid-containing holders having open upper sides and said second portions being received and extending upwardly beyond the upper sides of such holders.

22. Apparatus as defined in claim 21, wherein said holders include Walls having reinforcing ribs.

23. Apparatus as defined in claim 22, wherein at least some of said ribs extend into the fluid in the respective holders.

References Cited UNITED STATES PATENTS 2,620,918 12/1952 Fallon 2636X 2,883,171 4/1959 Munford 263-6B 2,916,276 12/1959 Cone et a1. 2636 JOHN J. CAMBY, Primary Examiner U.S. Cl. X.R. 198-218 

